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Abstract--Environmentally friendly technologies such as

photovoltaics and fuel cells are DC sources. In the current power

infrastructure, this necessitates converting the power supplied by

these devices into AC for transmission and distribution which

adds losses and complexity. The amount of DC loads in our

buildings is ever-increasing with computers, monitors, and other

electronics entering our workplaces and homes. This forces

another conversion of the AC power to DC, adding further losses

and complexity. This paper proposes the use of a DC distribution

system. In this study, an equivalent AC and DC distribution

system are compared in terms of efficiency.

Index Terms-DC power systems, power system modeling,

power distribution, losses

I. INTRODUCTION

ncreasing demand and environmental concerns have

forced engineers to focus on designing power systems

with both high efficiency and green technologies. Green

technologies are those that conserve natural resources such as

fossil fuels while reducing the human impact on the

environment through a reduction in pollution [1]. The most

well-known green technologies include photovoltaics andwind turbines. Although fuel cells are not considered a green

technology, fuel cells have low emissions compared to other

forms of energy and are deemed more environmentally

friendly. Unfortunately, the prevailing power system

infrastructures are based on alternating current (AC) while

two of the leading environmentally friendly energies, fuel

cells and photovoltaics, produce direct current (DC).

Currently, power system infrastructures that wish to

incorporate fuel cells and photovoltaics must first convert the

DC power produced by these energy sources to AC. This adds

complexity and reduces efficiency of the power system due to

the need of a power converter. Furthermore, an ever

increasing number of DC consuming devices such ascomputers, televisions, and monitors are being incorporated

into our buildings. The power supplied to these devices must

be converted again from AC back to DC adding further losses

and complexity to the power system.

Instead of using multiple converters to convert DC to AC

and then AC to DC, the power system could solely be based

on DC. This would eliminate the need for two sets of

converters for each DC load, reducing the cost, complexity,

and possibly increasing the efficiency. However, a definitive

analysis on a DC distribution system is needed to determine

the net benefits of eliminating the converters. In this paper, a

large steady state analysis of an existing AC grid is

constructed along with a DC counterpart. These models are

compared in terms of efficiency.

II. BACKGROUND

Since the development of electricity, AC has been depicted

as the better choice for power transmission and distribution.

However, Thomas Edison one of the founders of electricitysupported the use of DC. No method at that time existed for

boosting and controlling DC voltage at the load, so that

transmission of DC power from generation to load resulted in

a large amount of losses and voltage variations at the different

load locations. To resolve this issue, Westinghouse proposed

AC distribution. Nikola Tesla had only recently at that time

developed the transformer which had the capability of

boosting voltage in AC. This allowed for efficient

transmission of power from one location to another resulting

in a complete transformation of the power systems to AC [2].

Although many things have changed since the invention of

electricity, AC is still the fundamental power type of our

power infrastructure. However, due to the development of power converters and DC energy sources, interest in DC has

returned.

Several studies have investigated the use of a DC

distribution system. In [3], a small-localized DC distribution

system for building loads is investigated. This power system

is supplied by a DC distributed energy source for the DC

loads and has a separate AC grid connection for the AC loads.

The author relates that this methodology leads to a higher

efficiency compared to a system solely based on AC through

avoiding the use of the rectifier. The author notes that power

rectifiers have a relatively low efficiency compared to

inverters and DC-DC converters.

In [4], a DC zonal distribution system for a Navy ship isinvestigated to provide electrical isolation, reduce cost, and

increase stability. Essentially each zone has a separate

distribution system providing protection to the overall ship

power systems when an attack has occurred. Due to the need

of multiple levels of DC voltage, a DC system was deemed

superior to a AC system in terms of efficiency and cost. The

AC system would need an inverter and then DC-DC converter

for each DC bus voltage level, while a DC system would only

implement DC-DC converters.

AC vs. DC Distribution:

A Loss Comparison

Michael Starke1, Student Member, IEEE , Leon M. Tolbert

1,2, Senior Member, IEEE,

Burak Ozpineci2, Senior Member, IEEE,1

University of Tennessee,2Oak Ridge National Laboratory

I

978-1-4244-1904-3/08/$25.00 ©2008 IEEE



Nevertheless, several investigations in DC have suggested

that DC distribution is not as efficient. In [5], the authors

investigate DC distribution for a small-scale residential

system. The authors note that although conduction losses in a

DC system appear to be lower, the efficiency of power

converters during partial loading is a concern and can

ultimately lead to higher losses in DC. In [6], the author

compares several AC and DC systems for data centers. Based

on the results, the author concludes that a high voltage (HV)DC distribution system is more efficient than AC, but no

components need this high voltage. The author constructed

another DC system, coined a hybrid DC system, which

contained multiple DC voltages. However, the author

observed that the converter losses reduced the efficiency to

that below what is found in an equivalent AC system.

In all of these cases, a DC distribution system was

employed at systems below what is deemed the power

distribution level of the utility. Furthermore, the loads were

either assumed to be fully AC or DC. In this study, the utility

level distribution is considered, and efficiencies of the AC

and DC power systems are compared. The power system is

also adjusted for partial loading of AC and DC components.The goal is to relate an AC power system to DC in terms of

efficiency.

III. MODEL

To best represent the differences in AC and DC power

infrastructures, two models were created, one implementing

the actual AC devices and components of the grid and a

second model implementing DC devices. The DC model

adopts some of the AC components along with necessary DC

components to represent a direct conversion from an AC

system to a DC system.

The AC model is a representation of a large existing power

distribution system with thousands of loads in a variety of

sizes. The loads range in size from several watts to several

hundred kW and come from industrial motors, lighting,

computers, air conditioners, and other devices. Due to the

sheer number, the loads are not measured for each device

within the building, but instead are measured at the building

level. This results in a power system consisting of 235 loads

or buildings.

The loads employed have two sets of recorded data, a

maximum and an average. During a one year span, daily

maximum and average building loads of the power system in

question were measured. At the end of the year, the daily

averages were averaged and the maximum was found for the

whole year. The average and maximum instantaneous power

usage for the entire distribution system for the year are

31.9MVA/27.1MW and 42.6MVA/36.2MW, respectively.

The AC distribution power system under investigation is

divided into three voltage divisions, two medium

voltages(MV) and a low voltage(LV). For the AC power

system the HV and MV are 13.8kV and 2.4kV. The LV

magnitude is dependent on the building loads.

The DC model was constructed with the AC model in

mind. Any location where voltage was increased or decreased

with a transformer in AC, a DC/DC converter was

implemented in the DC model. AC components that are

deemed applicable in DC power systems were implemented in

the DC model and include the distribution lines and some

fault interrupting devices.

Both of these models were inserted into the SKM power

system analysis software package for analysis. This program

is a used extensively by the Oak Ridge National Laboratory

(ORNL) for AC power system power flow verification. This

software package accepts the input data from the user andimplements several numerical analysis techniques to

determine the voltage, current, and power levels at different

locations in the power system. The following subsections

describe the model in more detail.

A. AC Model

The components in the AC portion of the model that are

implemented in the load flow analysis are the distribution

line, transformer, AC load, and capacitor for Var

compensation as seen in Fig. 1. These components account

for more than 900 components in the model. Buses are also

necessary for analysis of the data and are placed in between

each load flow component. The total number of buses in themodel were determined to be 714. The fault interruption

devices in the model were ignored due to the negligible

resistance these devices add to the overall power system.

The characteristic data used to determine the load flow and

losses for the different components is described in Table I.

This data comes primarily from manufacturer-supplied data

with missing information supplied by test data.

TABLE I

AC DISTRIBUTION SYSTEM CHARACTERISITIC

COMPONENT DATADistribution Line Zero sequence impedance

Positive sequence impedance

Load Apparent Power

Power Factor

Voltage Rating

Transformer Zero Sequence impedance

Positive Sequence Impedance

Power Rating

Input/Output Voltage Rating

Capacitor Bank Zero sequence capacitance

Positive sequence capacitance

Load

0800 AREA

POLE 41A325 FTD

0800 AREA

0855 AREA

41-S47 41-F47 41-47

9321-41-47-SEC

LOAD-41-47

XLN-41-48

41-S48 41-F48

9330-41-48-PRI

41-48

9331-41-48-SEC

LOAD-41-48

41-S51 41-F51 41-51

9341-41-51-SEC

LOAD-41-51

Transformer

Bus

Distribution Line

Fig. 1. Portion of AC distribution system.



B. AC Model Equations

The basic methodology behind the SKM program is the use

of Ohm’s law. In matrix form this is:

[ ] [ ][ ]V Y I = (1)

where I represents the currents, V the voltages, and Y theadmittance matrix. The admittance matrix represents the

different admittance values that interconnect the buses in the

power system. These admittance values can come from a

number of sources, line impedance, impedance within a

transformer, or even shunt admittance from a capacitive

source. Consider the three bus example provided in Fig. 2.

The three bus example is composed of 3 lines that could be

considered as either a distribution line or a transformer. In

either case, a characteristic series impedance is associated

with these lines. Fig. 3 shows the admittance model.

Using Fig. 3, equations for the injected current at each bus

can be constructed in terms of the voltage and series andshunt admittance values. The following equations represent

the injected current for the three different buses.

32211211213)()()( V Y V Y V Y Y Y J J sha ×−+×−+×++=+ (2)

33231112321 )()()( V Y V Y Y Y V Y J J shb×−+×+++×−=+ (3)

32323123231)()()( V Y Y Y V Y V Y J J shc ×+++×−+×−=+ (4)

Manipulation of these equations into matrix form results in

the formation of the admittance matrix as shown below [7-8].

++−−

−++−

−−++

=

3

2

1

3232

3311

2121

3

2

1

*

V

V

V

Y Y Y Y Y

Y Y Y Y Y

Y Y Y Y Y

J

J

J

shc

shb

sha(5)

Since the voltages and current values are the unknown

values in the system, another equation must be adopted toresolve the equations. The following equation relates the real

and reactive power to current and voltage:

i

ii

iV

jQP I

)( +

=(6)

Combining equations 1 and 6 results in a nonlinear

equation as shown:

[ ] [ ]+

=

*

)(

V

jQPV Y (7)

This equation contains the variables of real and reactive

power, voltage (including magnitude and phasor angle), and

the admittance. Depending on the unknown and known

variables in this equation, the names swing bus, load bus, and

voltage control bus are provided as descriptions of the bus

type as shown in Table II.

TABLE II

AC BUS TYPESSpecified Free

Swing Bus Pl, Ql

V = 1 pu

= 0o

Pg, Qg

Load Bus Pg, = Qg = 0

Pl, Ql

V,

Voltage Control

Bus

Pg, Qg, Pl, V Qg,

Pg = real power generated

Qg = reactive power generated

Pl = real power consumed

Ql = reactive power consumed

V = voltage magnitude

= voltage angle

Since the base equation is nonlinear, an iterative numerical

technique must be implemented to solve for the solution. The

numerical analysis method implemented by SKM has been

coined the “double current injection” method. In this method,

the losses are originally assumed to be zero, and the current is

determined through calculation from the load and nominal

voltage values. The losses are then included and the voltage

drop at each load and bus is determined. The new voltages

lead to a recalculation of the current and another iteration is

begun. This process is repeated to a minimum error has been

reached.

Y1

Y3Y

2

Yshc

BUS 1

V1

BUS 2

V2

BUS 3

V3

J12 J

21

J13

J31

J32

J23

Yshb

Ysha

Fig. 3. Impedance schematic of 3 bus example

BUS 1 BUS 2

BUS 3

LINE 1

LINE 2LINE 3

Fig. 2. Schematic of 3 bus example.



C. DC Model

The components of the DC load model implemented in

load flow include the distribution line, DC/DC converter, and

DC load as seen in Fig. 4.

For this model several assumptions had to be made:

1) As with AC, the fault interruption devices were

deemed negligible in terms of losses and were

ignored in the model.

2) One current problem with DC-DC converters is that

the efficiency tends to fall when operated below the

rating. In the model implemented, the DC-DC

converter efficiency was assumed fixed for all

operating conditions. A paralleling topology

discussed in [9] describes a design that allows DC-

DC converters to operate close to the maximum

operating efficiency until as low as 10% of operation

as seen in Fig. 5.

3) The distribution lines used in the DC model are the

same as the AC model. Hence, the resistance values

employed come from the manufacturer specifications

of the AC distribution lines. The values used

represent the DC resistance of the conductor at a

temperature of 25oC.

4) Since DC is only composed of two cables instead of

the three used in AC, an extra cable exists for DC.

This extra cable is to be applied as a DC negative.

This provides DC with a positive, neutral, and

negative thereby doubling the apparent voltage [10].

5) Since no reactive power is produced or consumed in

a DC power system, the loads modeled in DC were of

the same real power magnitude. This power value

was determined by multiplying the apparent power of the AC load by the power factor.

The characteristic data for the DC model involves purely

resistive elements. SKM uses the equations in Table III to

convert the data supplied to a DC resistance. Since the DC-

DC converter model resistance is based on the rated power,

the simulation results must be verified to ensure that the

actual efficiency input was actually implemented.

TABLE III

DC COMPONENT CHARACTERISTIC EQUATIONSDistribution Line lr

cable×

LoadP

V 2

DC-DC Converter

P

V 2)1( η −

rcable – resistance/ft

l – length of cable in ft

V – rated voltage

P – rated power

η - rated efficiency

D. DC Model Equations

The DC load flow calculations are similar to those of the

AC power system with a few differences. The DC powersystem uses a conductance matrix instead of an admittance

matrix since no reactance exists in DC:

[ ] [ ][ ]V Y I = (8)

This embodies the DC system with a much simpler overall

equation and characterization of the buses. Table IV shows

the distinct bus types of a DC type. Unlike the AC system, the

DC system only has 2 bus types with 2 unknown variables.

SKM implements Newton Raphson to solve for these

variables.

TABLE IV

DC BUS TYPESSpecified Free

Swing Bus Pl

V = 1 pu

Pg

Load Bus Pg, Pl V

0 10 20 30 40 50 60 70 80 90 1000

10

20

30

40

50

60

70

80

90

100

E f f i c i e n c y ( % )

Converter Rating(%)

Single Converter

4 Converters

Fig. 5. Efficiency curves for DC-DC converter.

0800 AREA

POLE 41A

0800 AREA

0855 AREA

41-S47 F-41-008

41-S48 F-41-009

41-S51 F-41-010

dcCBL-41-013

dcBUS-41-020

dcCNV-41-008

dcBUS-41-019

dcCNV-0009

dcBUS-41-021

dcCNV-41-010

dcBUS-41-023

dcCLD-41-007

dcCLD-41-008

dcCLD-41-009

DC LoadDC/DC Converter

DC Cable

Fig. 4. Portion of DC distribution system.



E. Difference in AC and DC

In terms of the basic power system equations, AC and DC

power systems have quite a contrast. In an AC system, power

flow is often determined by the equation:

)cos(33 θ φ ×××= RMS RMS I V P (9)

where VRMS, IRMS, and θ are the respective voltage in RMS,

current in RMS, and power factor angle. In DC, the power

flow is calculated by:

I V P DC ×= (10)

Upon examination, these equations can have a substantial

difference in power flow. Depending on the power factor,

AC can have three times more power flow when the same

RMS voltage and current are implemented in an AC and DC

system as shown:

)cos(3

3

θ

φ =

DC P

P(11)

The voltage and currents in the DC system must be

adjusted to overcome this difference. If we now consider the

difference in losses for AC and DC:

AC RMS AC R I P ××=2

3 3φ (12)

DC DC DC R I P ××=

22 (13)

and if we wish the systems to have the same losses:

82.32 ≈=

DC

RMS AC

I

I (14)

where the AC and DC resistance values are assumed to be the

same, a noticeable gain in DC can be seen. This result shows

that the DC current can be 1.22 times larger than the AC

current and the system will have the same conduction losses.

If a DC neutral is implemented as previously discussed,

and the equations (9),(10), and (14) are combined:

)cos(

82.

2 θ =

DC

RMS AC

V

V (15)

and if we convert the voltages from RMS to peak:

)cos(

15.1

2 θ ≈

DC

AC

V

V (16)

This illustrates that if the same peak voltages in both the

AC and DC systems are implemented, DC should have a

small advantage over AC in terms of transmission losses

when implementing AC cables. Nevertheless, the

transmission losses tend to only account for a small

percentage of the system losses. The power conversion

devices have a more significant impact.

In AC, the power conversion devices employed are

transformers. The efficiency of the transformer over the years

has improved dramatically, particularly in upper level power

systems. These devices now have efficiency upwards of 98%.

Unfortunately to convert back to DC, AC power systems use

rectifiers that are much lower in efficiency. In this study the

rectifiers are assumed to be 90% efficient [3].DC on the other hand employs DC-DC converters with

overall efficiencies that tend to be below 95% and as

mentioned, suffer from decreased efficiency when operated

below rating unless special implementation of the converter is

performed. To convert back to AC, inverters are necessary. In

this study, the inverters are assumed to have efficiencies of

97%.

Based on the varying efficiencies of the power converting

technologies, and the use of multiple converters in each

system, it is difficult to distinguish one type of power over the

other based on a simple calculation. Instead a power system

must be analyzed to determine the system that has the better

results.The following section relates the outcome of the

comparison of the power systems.

IV. RESULTS

For the comparative study, the efficiency rating of the DC-

DC converters were assigned to three different efficiencies,

95%, 97%, and 99.5%. The voltages of the DC system were

varied to represent the I2R losses and the total losses are

provided in kW. The data for a power system supplied by a

DC source, with DC components, and DC loads based on

maximum operation is shown in Fig. 6.

The equivalent AC system with an AC source, AC

components, and AC loads resulted in 800 kW of losses.

Table V shows the results. Based on a straight comparison of

0.00

500.00

1000.00

1500.00

2000.00

2500.00

3000.00

3500.00

12 14 16 18 20 22 24 26 28 30

System Voltage (kV)

L o s s e s ( k W )

99.5% 97% 95%

Fig 6. DC power system efficiency for maximum operation.



a 100% AC system and a 100% DC system, AC would have

fewer losses.

When adjusted to the average power, the AC power system

again had fewer losses than the DC power system. Fig. 7

shows the losses of a 100% DC system. The equivalent AC

system average system losses were determined to be 412 kW

as shown in Table VI.

TABLE VLOSSES BASED ON MAX LOADING OF PURE AC AND

DC POWER SYSTEMS

System VoltageSystem

Type 13.8kV 18kV 24kV 30kV

AC 800 - - -

95%1 DC 3332 2799 2496 2354

97%1DC 2204 1716 1427 1296

99.5%1 DC 1121 651 386 263

1represents DC-DC converter efficiency

TABLE VI

LOSSES BASED ON AVG LOADING OF PURE AC AND

DC POWER SYSTEMS

System VoltageSystem

Type 13.8kV 18kV 24kV 30kV

AC 412 - - -

95%1 DC 2181 1892 1712 1614

97%1DC 1500 1223 1053 977

99.5%1 DC 630 370 198 133

1 represents DC-DC converter efficiency

Although this would seem detrimental to the application of

a DC distribution system, another comparison is needed. To

form a realistic study, the model of the power system should

be composed of partial loads of both AC and DC

components. Therefore, a partial loading of the different load

types was examined based on the average model data, where

the AC system is based on 13.8 kV and the DC system with

30 kV. This met with much better results in terms of the

application of DC distribution as shown in Table VII.

Table 7 illustrates that when 50% of the loads are AC and

50% of the loads are DC, the difference in losses becomes

relatively close with a 95% DC-DC converter. A better

representation is shown in Fig. 8. DC distribution actually has

lower losses when more than 50% of the loads are DC and

DC- DC converters with efficiencies of 95% or higher are

used.

TABLE VII

LOSSES BASED ON PARTIAL AC AND DC LOADING

OF POWER SYSTEMS

Loads AC(kW) DC(kW) DC(kW) DC(kW)

AC%/DC% 95%1 97%1 99.5%1

100/02

412 2317 1811 1119

50/502

1679 1982 1313 583

0/100 2 2872 1653 1008 3291 represents DC-DC converter efficiency2

represents ratio of AC/DC loads

V. CONCLUSION

Under the current power system infrastructure, DC sources

that supply DC loads must implement two converters, one

that first converts the DC to AC and then another to return

the AC back to DC. This type of power system can result in

significant losses.

As this study shows, AC and DC distribution systems can

have the same merit when the loads are equal in ratio, 50%

AC loads and 50% DC loads. Nevertheless, this study

assumed that AC power system was supplied by a AC source

and DC through a DC source. If the AC power system is

supplied by a DC source, further losses can be expected

resulting in further benefits of a DC distribution system.

One other possibility in increasing the system benefits is

offering two types of power for every load, AC and DC. As

shown each has a substantial benefit in supplying their own

loads and this can result in a significant reduction in power

system losses.

0.00

500.00

1000.00

1500.00

2000.00

2500.00

12 14 16 18 20 22 24 26 28 30

System Voltage (kV)

L o s s e s ( k W )

99.50% 97% 95%

Fig 7. DC power system efficiency for average operation.

0

500

1000

1500

2000

2500

3000

3500

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

% DC Loads

L o s s e s ( k W )

AC Losses DC Losses (95%) DC Losses (97%) DC Losses (99 .5%)

Fig 8 Partial AC and DC loading of power systems.



Ultimately, the defining device in the possible application

of a DC distribution system is the DC-DC converter.

Although the data analyzed considered DC-DC converters

with efficiencies with 95% or higher, actual DC-DC

converters rarely meet 95% efficiency. To substantiate a DC

distribution system, advancements in DC-DC converter

technology are significantly needed.

VI. REFERENCES [1] http://en.wikipedia.org/wiki/Environmental_technology , Wikipedia, 2007.

[2] http://en.wikipedia.org/wiki/Thomas_Edison , Wikipedia, 2007.

[3] H. Pang, E. Lo, B. Pong, “Dc Electrical Distribution Systems in

Buildings,” International Conference on Power Electronics Systems,

Nov. 2006, page(s): 115-119.

[4] J. Ciezki, R. Ashton, “Selection and Stability Issues Associated with a

Navy Shipboard DC Zonal Electric Distribution System,” IEEE

Transactions on Power Delivery, vol. 15, no. 2, Apr 2000, page(s): 665-

669.

[5] K. Engelen, E. Shun, P. Vermeyen, I. Pardon, R. D’hulst, J Driesen, R.

Belmans, “The Feasibility of Small-Scale Residential DC Distribution

Systems,” IEEE Industrial Electronics Conference, Nov 2006, page(s):

2618-2632.

[6] N. Rasmuseen, “AC and DC Power Distribution for Data Centers,” APC

White Paper #63.

[7] J. Grainger, W. Stevenson, Power Systems Analysis, McGraw-Hill, 1994.[8] M. Crow, Computational Methods for Electric Power Systems, CRC

Press, 2003

[9] General Motors Corporation, “High efficiency power system with plural

parallel DC/DC converters,” US Patent 6 166 934, Jun. 30, 1999.

[10] D. Nilsson, “DC Distribution Systems,” Ph.D. Dissertation, Department

of Energy and Environment, Chalmers University of Technology,

Goteborg, Sweden, 2005.

BIOGRAPHIES

Michael R. Starke (S 2004 – M 2006) received the

B.E. and M.S., in electrical engineering from the

University of Tennessee, Knoxville, Tennessee.

He presently is a Ph.D. student in electrical

engineering at The University of Tennessee. Hisresearch interests include alternative energies, power

systems, and power electronics interface with

utilities.

Leon M. Tolbert (S 1989 – M 1991 – SM 1998)

received the B.E.E., M.S., and Ph.D. in Electrical

Engineering from the Georgia Institute of

Technology, Atlanta, Georgia.

Since 1991, he worked on several electrical

distribution projects at the three U.S. Department of

Energy plants in Oak Ridge, Tennessee. In 1999, he

joined the Department of Electrical and Computer

Engineering at the University of Tennessee,

Knoxville, where he is presently an associate

professor. He is an adjunct participant at the Oak Ridge National Laboratory.He does research in the areas of electric power conversion for distributed energy

sources, reactive power compensation, multilevel converters, hybrid electric

vehicles, and application of SiC power electronics.

Dr. Tolbert is a registered Professional Engineer in the state of Tennessee.

He is the recipient of a National Science Foundation CAREER Award and the

2001 IEEE Industry Applications Society Outstanding Young Member Award.

Burak Ozpineci (S’92–M’02–SM’05) received the

B.S. degree in electrical engineering from the

Middle East Technical University, Ankara, Turkey,

in 1994, and the M.S. and Ph.D. degrees in electrical

engineering from the University of Tennessee,

Knoxville, in 1998 and 2002, respectively.

He joined the Post-Masters Program with the Power Electronics and Electric

Machinery Research Center, Oak Ridge National Laboratory (ORNL),

Knoxville, TN, in 2001 and became a Full-Time Research and Development

Staff Member in 2002. He is also an Adjunct Faculty Member of the University

of Arkansas, Fayetteville. He is currently doing research on the system-level

impact of SiC power devices, multilevel inverters, power converters for

distributed energy resources, and intelligent control applications to power

converters.

Dr. Ozpineci was the Chair of the IEEE PELS Rectifiers and Inverters

Technical Committee and Transactions Review Chairman of the IEEE Industry

Applications Society Industrial Power Converter Committee. He was the

recipient of the 2006 IEEE Industry Applications Society Outstanding Young

Member Award, 2001 IEEE International Conference on Systems, Man, and

Cybernetics Best Student Paper Award, and 2005 UT-Battelle (ORNL) Early

Career Award for Engineering Accomplishment.

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